alprostadil: clinical use

Prescribing considerations

• Investigate and manage reversible causes of erectile dysfunction before treatment.
• Assess whether sexual activity is safe, particularly with unstable cardiovascular, cerebrovascular or significant cardiopulmonary disease.
• Initiate and teach intracavernosal administration under clinical supervision; reinforce aseptic technique, site rotation and safe sharps disposal.
• Assess bleeding risk and concomitant anticoagulant or antiplatelet treatment.
• Neonatal infusion requires trained staff, meticulous dilution and immediate access to ventilation and paediatric intensive care.

Contraindications and cautions

• Hypersensitivity to alprostadil or formulation excipients.
• For erectile products: disorders predisposing to priapism, including sickle-cell disease or trait, multiple myeloma and leukaemia.
• For injections: penile anatomical deformity, cavernosal fibrosis, Peyronie's disease or penile implant.
• Vitaros has additional product-specific exclusions including urethritis, balanitis, severe hypospadias, hyperviscosity or thrombotic predisposition, orthostatic hypotension, previous syncope and myocardial infarction.
• Erectile formulations should not be used when sexual activity is contraindicated.

Monitoring

• Erection duration and access to urgent management of priapism.
• Penile pain, injection-site bleeding, nodules, curvature and fibrosis during follow-up.
• Blood pressure or syncope symptoms where clinically relevant.
• During neonatal infusion: respiratory status, heart rate, blood pressure, temperature, oxygenation and biochemical response, with ventilation immediately available.

Clinical pharmacology

Alprostadil is prostaglandin E1. It raises cyclic AMP in target smooth muscle, causing vasodilation; local penile delivery relaxes cavernosal tissue, while systemic neonatal infusion maintains ductal patency. It is rapidly metabolised, principally by the lungs, liver and kidneys.

Formulation and product differences

• Neupedix is an ethanol-containing sterile concentrate requiring dilution for specialist neonatal infusion.
• Vitaros is a refrigerated, single-use cream applied to the urethral opening; partner exposure and condom precautions are formulation-specific.
• Alprostadil injection powder is reconstituted from a vial and used immediately.
• Viridal Duo uses a double-chamber cartridge containing an alprostadil–alfadex complex and solvent with a reusable injector system.
• Caverject Dual Chamber combines powder and benzyl-alcohol-containing diluent in a dual-chamber cartridge.

Cream

Route: Cutaneous

Strengths: 3 mg/g

Solution for infusion

Route: Intravenous

Strengths: 500 micrograms/mL

Injection

Route: Parenteral

Strengths: 10 micrograms, 10 micrograms/mL, 20 micrograms, 20 micrograms/mL, 40 micrograms/mL